A union that represents 775 staff members at the University of Illinois at Urbana-Champaign plans to start a three-day strike on Monday.

Members of the Service Employees International Union Local 73, whose duties include food service and custodial work, have been negotiating a new contract with the university for almost a year. With no deal in sight and no further negotiations scheduled, a majority of members voted to authorize the strike.

Union spokesman Adam Rosen warns that dorms won’t be cleaned, meal service will be impeded and campus mail delivery stalled until workers return to their posts Thursday. He said about 75 percent of union members have signed up to picket the campus.

University spokeswoman Robin Kaler said food service will continue and administrators will reassign staff to perform striking workers’ “most essential services.”

“We certainly don’t intend for it to affect students,” she said. “It’s the week before spring break. We’ll serve food – hot food. We’ll maintain the halls as best we can.”

When the same union went on a three-day strike last year at the University of Illinois at Chicago, about three-quarters of members participated. Rosen said he expects full participation in this week’s strike.

Kaler said the university is prepared to resume negotiations “whenever the union is ready to talk to us.” Rosen said the college should approach union members with a fair offer.